1. Field of the Invention
The present invention relates to a method of producing split bearing rings and, more particularly, it relates to a method of splitting bearing rings in a direction obliquely crossing their axes by exerting wedge stress in a notch of substantially V-shaped cross-section formed in a peripheral or end surface of a bearing ring.
2. Description of the Prior Art
Generally, in a split bearing ring, splitting is effected by forming a notch in an end surface or inner peripheral surface of a bearing ring to be split, and then applying a ring press-breaking method using a press. According to this conventional method, since it is difficult to split a ring obliquely or in a V-form at a predetermined angle with respect to the axis of the ring (oblique splitting), in the case of a thin-walled article, it is usual practice to form a notch in the inner peripheral surface or an end surface and split the ring axially (parallel splitting) by pressing it in a direction crossing the notch at right angles. However, in the case of a thick-walled article, splitting is effected usually by turning. With this method by turning, however, although oblique splitting is possible by separately producing two rings, each having an end surface inclined with respect to the axis by turning, the yield of material is low. Thus, the method is disadvantageous from the standpoint of productivity.
In addition, in splitting bearing rings, oblique splitting may be said to be the most desirable splitting method in light of the following conditions:
The split line resulting from oblique splitting crosses the major axis of the contact ellipse at an angle on the bearing rolling surface and the contact surface contacts only a portion of the split line with respect to line contact or similar rolling contact, so that stress concentration at the split region can be greatly reduced, resulting in remarkable improvement of the life of the bearing.